Never knew that rubbing perfume damages the scent, but it makes sense. I've always sprayed my wrists and swiped them against my neck.

So is dabbing it on your skin out of the question also? My signature scent (Frederic Malle Musc Ravageur) is very potent, so if I sprayed each wrist and both sides of my neck, I would smell like a prostitute.

isn't eau de toilette and parfum the same..
and cologne is just a masculin version of parfum?

...also (after the reply by fashionista-ta) the name references how the long the scent lasts, parfums can last upto around 8 hours i believe, I can't remember Eau de Toilettes but i think its around 4-5.
It's strange though, i have Paco Robanne 1 Million and i can often smell it a day or two after spraying it aswell (yes i do wash!) thats an Eau de Toilette.

Eau de Cologne, Eau de Toilette, Eau de Parfum and Pure Parfum (or Extrait) refer to the concentration of perfume oils in the scent.

EdC is typically no more than 3-5% perfume oil, EdT 5-15%, EdP 15-20%, anything above that can be considered parfum. However, these boundaries are not firm.

More importantly, they do not absolutely dictate how strong the perceived scent is, or how much "throw" (sillage) it has. The specific ingredients and the formulation play a big part. Some EdTs may appear more potent than some EdPs.

Usually scents with a higher concentration of perfume oil will last longer than those with less. It is also worth noting that, when multiple concentrations of a scent are available, they do not all necessarily have the balance of ingredients. Guerlain Jicky is a classic example of this, with the civet being most pronounced in the Eau de Parfum concentration.

I used to spray my wrists, pat my wrists together lightly, and then touch them against my neck behind my ears; however, I disliked that the sleeves of my jackets would retain the scent. I like to rotate between fragrances and having my sleeves become a salad of fragrances dissatisfied me. Nowadays I just spray my chest.

About the number of sprays; different size bottles, or more accurately, different size uptubes will deliver different amounts of scent per spray depending on their size (volume.) So a spray from a small sample sprayer delivers less fragrance than a spray than a 50ml bottle, and a 100ml bottle will typically deliver more than the 50ml bottle. Therefore the number of sprays desired depends on the size of the bottle, as well as the strength of that particular scent.